JP2993827B2 - Work roll cross type rolling mill, rolling equipment and rolling method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling mill for crossing work rolls having an excellent ability to control a strip of rolled material, and more particularly to a work roll cross type rollable lubrication between a reinforcing roll and a work roll. TECHNICAL FIELD The present invention relates to a rolling mill, a rolling facility provided with at least one rolling mill, and a rolling method.

[0002]

2. Description of the Related Art As a rolling mill of a type in which work rolls cross each other, there is a rolling mill in which only work rolls are crossed as described in JP-A-47-27159.

[0003] In addition, Mitsubishi Heavy Industries Technique Vol. 21, No.
As described in 6, the roll set of the pair of the upper working roll and the upper reinforcing roll and the roll set of the pair of the lower working roll and the lower reinforcing roll are integrally formed, and the axes of the paired rolls are mutually crossed (crossed). Machines are known.

Further, as described in JP-A-3-234305, in a four-high rolling mill in which work rolls are crossed, the thrust force applied to the work rolls in a kiss roll state after the rolled material has been removed is reduced. For applying a lubricant for the purpose, as described in Japanese Patent Application Laid-Open No. 61-7709, in a normal four-high rolling mill in which work rolls do not intersect, work rolls and One in which a coolant is applied to a reinforcing roll and a lubricant as rolling oil is separately supplied between a work roll and a rolled material. Further, as described in JP-A-47-27849, the rolled material is rolled into a roll. Some supplies a lubricant as rolling oil only when they are in contact.

[0005]

Problems to be Solved by the Invention
In the work roll cross-type rolling mill described in JP-A No. 9-2003, it was expected that the need for various sheet crown materials could be met by crossing the upper and lower work rolls at various angles and changing the roll gap of the work rolls. . However, in practice, the thrust force generated by the relative slip between the work roll and the reinforcing roll becomes extremely large, and practical use has been difficult.

[0006] Mitsubishi Heavy Industries technique Vol. 21, No. In the rolling mill described in No. 6, the work roll and the reinforcing roll are formed as an integral pair, and the pair of rolls is crossed. Therefore, there is no relative slip between the work roll and the reinforcing roll, and no large thrust force is generated. However,
Since the work roll and the reinforcing roll are integrally crossed, the center of the metal chocks of the reinforcing roll that directly receives the rolling load is displaced from the center of the screw, and a moment is generated, thereby preventing a smooth operation of the rolling. For this reason, a structure in which a beam having a large rigidity is provided to balance is used, but there is a problem that the rolling mill is inevitably complicated and large.

The prior art described in the above-mentioned Japanese Patent Application Laid-Open No. 3-234305 is effective in reducing the thrust force applied to the work roll in the kiss roll state, but has a problem with the thrust force between the work roll and the reinforcing roll. Does not solve the problem. Further, the prior arts described in JP-A-61-7909 and JP-A-47-27849 do not solve the problem relating to the thrust force between the work roll and the reinforcing roll.

[0008] As a simpler method of reducing the thrust force than the above prior art, the present applicant keeps the reinforcing roll parallel, crosses only the work roll, and puts a lubricant between the work roll and the reinforcing roll. A rolling mill of a supply type (hereinafter referred to as a work roll cross type rolling mill) has been invented and filed (Japanese Patent Application No. 4-20956). In this scheme,
Instead of eliminating the relative slip between the work roll and the reinforcing roll, the lubricant is supplied to reduce the thrust force itself caused by the relative slip. By using this method, the thrust force can be reduced relatively easily, so that the structure can be relatively simplified and the rolling mill can be reduced in size.

However, it has been found that the prior invention has room for further improvement in terms of the lubricant supply device and the lubricant function.

That is, in a normal rolling mill, a coolant (cooling water) is sprayed on the work roll to cool the work roll. For this reason, in the work roll cross type rolling mill of the prior application, the coolant forms a water film and adheres to the surface of the work roll to be carried between the work roll and the reinforcing roll, or the sprayed coolant is used for the work. There is a problem that it directly penetrates between the roll and the reinforcing roll, and the coolant is mixed into the lubricant, so that it is difficult to reliably perform the lubrication function.

[0011] Further, the invention of the prior application provides a lubricant between a work roll and a reinforcing roll (hereinafter, appropriately referred to as a roll) by supplying a lubricant based on mineral oil which loses lubricity at a high temperature. While reducing the thrust force of the hot rolled material. However, the reduction of the thrust force between the rolls and the securing of the biting capacity are the minimum conditions that can be satisfied for realizing a work roll cross type rolling mill, and when applied to actual machines, severe rolling loads and speeds are required. It is necessary to satisfy such conditions that a stable operation can be performed for a long time by withstanding the use conditions of the above and that the treatment of the cooling water mixed with the lubricant is easy.

That is, the lubricating agent satisfies the above-mentioned conditions of the biting and the thrust force, and further ensures that a friction coefficient that does not cause slip between the rolls during acceleration or deceleration of the rolls can be ensured. No vibrations due to speed are generated. ・ There is no clogging in the piping and nozzles of the lubricant supply device.
Lubricant has good fluidity to be evenly applied in the axial direction of the roll surface.-Lubricating oil mixed in a large amount of coolant (cooling water) can be relatively easily separated by a separating coagulant or the like. It is indispensable to satisfy such conditions.

A first object of the present invention is to provide a work roll cloth type rolling mill, a rolling equipment capable of improving a lubricant supply device, and reliably performing lubrication between a work roll and a reinforcing roll. It is to provide a rolling method.

A second object of the present invention is to provide a work roll cloth type rolling mill which improves the function of a lubricant, enables a stable operation as a rolling mill, and facilitates processing of a lubricant mixed with a lubricant. And a rolling method.

[0015]

According to the present invention, in order to achieve the first object, a pair of work rolls, a pair of reinforcing rolls respectively supporting these work rolls, a rolling mill outlet side or an input side. Cooling means for injecting a coolant from the sides to the pair of work rolls to cool them, the pair of work rolls having their axes intersecting with the axes of the pair of reinforcing rolls, respectively. In a work roll cross-type rolling mill arranged obliquely in a horizontal plane such that the axes of the work rolls cross each other, the work rolls are arranged so as to face each of the pair of reinforcing rolls, and the pair of work rolls and the pair A lubricant is supplied to a position on the surface of the reinforcing roll remote from the respective contact position between the reinforcing roll and the lubricating roll to lubricate between the work roll and the reinforcing roll. Work, characterized in that it comprises a device roll cross rolling mill is provided.

Preferably, each of the lubricant supply devices is arranged so as to surround a lubricant nozzle for spraying a lubricant to a position on the surface of the reinforcing roll, and a lubricant sprayed from the lubricant nozzle. A cover for collecting excess lubricant therein, sealing means provided at an end of the cover facing the reinforcing roll to seal the inside of the cover, and an excess lubricant collected inside the cover. And a lubricant discharge passage for discharging.

In the above, preferably, the sealing means includes a flexible material that comes into contact with the reinforcing roll, or a slit that injects a high-pressure gas to the reinforcing roll.

[0018] Preferably, further, the surface of the work roll is located just before the contact position between the work roll and the reinforcing roll as viewed in the rotation direction of the pair of work rolls on the exit side of the rolling mill. A first drainer is disposed so as to be in contact with each other and shuts off the coolant so that the coolant injected to the work roll does not enter the contact position.

[0019] Preferably, the work rolls are further arranged so as to be in contact with the surfaces of the pair of reinforcing rolls, respectively, are sprayed on the pair of work rolls, adhere to the surfaces thereof, and rotate with the work rolls and the reinforcing rolls. A second draining means is provided for removing the coolant so that the carried coolant is not brought into a position where the lubricant supply device is arranged.

Preferably, the lubricant supplied from the lubricant supply device is based on mineral oil to which an ester is added, and the addition of a surfactant and a fatty acid for improving emulsifiability is minimized. Including lubricating crude oil.

Preferably, the lubricant supplied from the lubricant supply device is under the following conditions: (a) the friction coefficient between the work roll and the reinforcing roll is 0.04 to 0.1;
1, (b) a viscosity of 80 Cst. Or less at 40 ° C., (c) a mineral oil and 5% or more of synthetic ester as a base oil, and (d) a fatty acid as an oiliness improver. 0.03% to 0.5%, and (e) 0.1% or more of the extreme pressure additive.

In the above, preferably, the lubricating crude oil does not contain (f) a surfactant as an emulsifier in an amount of 0.5% or more.

In the above, the lubricant supplied from the lubricant supply device is preferably a highly separable emulsion obtained by diluting the lubricating crude oil with water.

The lubricant supplied from the lubricant supply device may include a lubricating crude oil containing a mineral oil as a base and a surfactant or a fatty acid added thereto to improve emulsifying properties. May be diluted with water to obtain an emulsion liquid having good emulsion stability.

Preferably, the pair of reinforcing rolls have a roll surface deformed by a rolling load and a roll bending force at both ends thereof at both ends thereof, and an axis of the reinforcing roll and a working roll supported by the reinforcing roll. Has a tapered portion that does not make surface contact with the work roll even when the axis of the seal member approaches, and a portion of the sealing means facing the tapered portion is shaped to contact along the tapered portion.

According to the present invention, in order to achieve the first object, according to the present invention, there is provided a work roll cloth type rolling mill as described above, and a lubricant for storing excess lubricant collected by the lubricant supply device. A rolling facility comprising a tank and a lubricant circulation system having a pump for supplying lubricant to the lubricant supply device is provided.

According to the present invention, in order to achieve the first object, according to the present invention, at least one work roll cross type rolling mill as described above is installed so as to be capable of tandem rolling, and is further collected by the lubricant supply device. And a lubricant circulation system having a lubricant tank for storing the excess lubricant and a pump for supplying the lubricant to the lubricant supply device.

According to the present invention, there is provided a rolling method for a rolling mill comprising a pair of work rolls and a pair of reinforcing rolls respectively supporting the work rolls. Injecting a coolant to the pair of work rolls from the outgoing side or the inlet side to cool them, a reinforcing roll surface separated from a contact position between the pair of work rolls and the pair of reinforcing rolls Injecting a lubricant to the upper position to lubricate between each work roll and the reinforcing roll, at the same time, the axes of the pair of work rolls intersect with the axes of the pair of reinforcing rolls, respectively. And a rolling method characterized by controlling the inclination of the pair of work rolls in a horizontal plane to control the sheet crown of the rolled material so that the axes of the work rolls cross each other. It is subjected.

In order to achieve the second object, according to the present invention, a pair of work rolls and a pair of reinforcing rolls respectively supporting these work rolls are provided. In a work roll cross type rolling mill, the axes of the pair of reinforcing rolls intersect with the axes of the pair of reinforcing rolls, respectively, and the axes of the work rolls intersect with each other. A lubricant supply device for supplying a lubricant between the roll and the pair of reinforcing rolls, wherein the lubricant has the following conditions, and (a) a friction coefficient between the work roll and the reinforcing roll is 0. In the range of 04 to 0.1,
(B) a viscosity of not more than 80 Cst. At 40 ° C., (c)
Mineral oil and 5% or more synthetic ester as base oil, and (d) fatty acid as oil improver in an amount of 0.03-0.
A work roll cloth type rolling mill characterized by containing lubricating crude oil satisfying 5% and (e) containing 0.1% or more of an extreme pressure additive.

Preferably, in the above work roll cross type rolling mill, the pair of work rolls are:
Further, the pair of work rolls are configured to be movable in the roll axis direction.

In the above, preferably, the lubricating crude oil does not contain 0.5% or more of a surfactant as an emulsifier.

According to the present invention, there is provided a rolling method for a rolling mill comprising a pair of work rolls and a pair of reinforcing rolls respectively supporting the work rolls. Injecting a coolant to the pair of work rolls from the machine exit side or the entrance side to cool them, while supplying a lubricant between the pair of work rolls and the pair of reinforcing rolls, Controlling the inclination of the pair of work rolls in a horizontal plane so that the axes of the work rolls intersect with the axes of the pair of reinforcing rolls and the axes of the work rolls intersect with each other; , And using a lubricating crude oil or an emulsion thereof satisfying the above conditions (a) to (e) as the lubricant.

Preferably, in the above-mentioned rolling method, the inclination of the pair of work rolls is controlled, and the amount of movement of the work rolls in the roll axis direction is controlled to control the sheet crown of the rolled material. A rolling method is provided.

In the above, preferably, the lubricating crude oil does not contain 0.5% or more of a surfactant as an emulsifier.

[0035]

The operation of the present invention to achieve the first object is as follows. In the present invention configured as described above, at a position on the surface of the reinforcing roll remote from the contact position of the work roll and the reinforcing roll of the work roll cross-type rolling mill, by injecting a lubricant from a lubricant supply device, The lubricant sprayed on the surface of the reinforcing roll is carried to the contact position between the work roll and the reinforcing roll with the rotation of the reinforcing roll, and lubrication between these rolls is performed. As a result, the lubricant is reliably applied to the roll surface (hereinafter, referred to as plate-out) without being disturbed by the coolant accumulated at the contact position between the work roll and the reinforcing roll. It is possible to effectively reduce the thrust force generated between the and the reinforcing roll.

In the lubricant supply device, the lubricant is sprayed to the above-mentioned position on the surface of the reinforcing roll by the lubrication nozzle and supplied to the roll surface. The cooling is performed in the closed space formed by the lubricant and the roll surface, so that the coolant of the work roll is not mixed with the injected lubricant, and the adhesion of the lubricant to the roll surface is improved. In addition, the excess lubricant among the lubricant sprayed on the roll surface is prevented from scattering to the outside, the amount of lubricant mixed in the coolant can be reduced, and the treatment of the coolant becomes easy. In addition, the lubricant sprayed toward the reinforcing roll flows down without adhering to the roll surface, and excess lubricant collected inside the cover is discharged from the lubricant discharge passage.

Further, the inside of the cover is sealed by a sealing means provided at the end of the cover facing the reinforcing roll, so that coolant is prevented from being mixed into the lubricant and the lubricant is scattered to the outside. Is done. Further, the water film remaining on the surface of the reinforcing roll is also removed by the sealing means. Therefore, the injection of the lubricant and the plate-out inside the cover are reliably performed.

The sealing means is preferably of a contact type using a flexible material that comes into contact with the reinforcing roll, or a non-contact type of jetting high-pressure gas from the slit to the surface of the reinforcing roll. The function of the means is fulfilled.

Further, the coolant sprayed on the work roll is cut off immediately before the contact position between the work roll and the reinforcing roll by the first draining means provided on the work roll surface on the exit side of the rolling mill, and the coolant is removed. There is no possibility that the lubricating property is deteriorated by entering into this portion. Further, the coolant does not directly adhere to the reinforcing roll, and the inter-roll lubricant that has been plated out as described above is not washed away.

The coolant sprayed on the work rolls on the entry side of the rolling mill and adhered to the surface of the work rolls forms a water film and is carried along with the rotation of the work rolls and the reinforcing rolls. The second provided to contact the
And is prevented from being brought into the position where the lubricant supply device is provided. This ensures that the plate-out of the lubricant is performed without being disturbed by the water film.

Even if a water film still exists on the roll surface by the sealing means and the first and second draining means as described above, the lubricant is sprayed from the lubrication nozzle in a spray form. As a result, the water film is pierced and the lubricant is reliably plate-out on the roll surface.

Further, when the roll surface is deformed by Hertz due to the rolling load and the roll bending force and the center between the reinforcing roll and the work roll approaches, both ends of the reinforcing roll are greatly deformed, and the sealing means at this portion fulfills the function. May disappear. In the present invention, the tapered portion is provided at both ends of the reinforcing roll, and even in the case described above, the tapered portion is prevented from being brought into surface contact with the work roll. The sealing means, which is in contact form, performs its function.

In the present invention, the excess lubricant collected in the lubricant discharge passage is collected in the lubricant tank, and the lubricant is supplied to the lubricant supply device from the lubricant tank. Is used repeatedly. Therefore, the amount of the lubricant mixed in the coolant can be reduced, and the treatment of the coolant becomes easy. Further, lubrication is performed with a minimum necessary amount of lubricant without wasting a large amount of lubricant.

The operation of the present invention to achieve the second object is as follows. Generally, in a work roll cross type rolling mill,
The thrust force applied to the work roll is the difference between the thrust force from the reinforcing roll and the thrust force from the rolled material. In the present invention configured as described above, the coefficient of friction (corresponding to the thrust force from the reinforcing roll) between the working roll and the reinforcing roll is set to 0.1 or less, so that the thrust load applied to the working roll is reduced. It becomes 5% or less of the rolling load at the maximum, and can be kept within the range of the load capacity of a normal work roll. Further, according to this condition, the frictional force between the work roll and the reinforcing roll can be reduced, and the vibration caused by the stick-slip using the elastic deformation of the roll surface in the axial direction as a spring does not occur.

Further, since the reinforcing roll having a large inertia is driven by the work roll, if the friction coefficient between the rolls is small, slip occurs and the surface of the reinforcing roll is locally worn. Normally, a relatively large force corresponding to the balance force of the work roll is applied to the reinforcing roll, but even in this case, the resistance (friction coefficient 0.01
), Inertia torque required for acceleration (friction coefficient 0.02
It is necessary to drive the reinforcing roll by overcoming this problem. In the present invention, by setting the friction coefficient between the work roll and the reinforcing roll to 0.04 or more, it is possible to drive the reinforcing roll by overcoming the resistance or inertia torque of the seal of the bearing of the reinforcing roll and the like. The reinforcing roll does not slip during acceleration after biting of the rolled material and deceleration after falling off the tail.

Further, the base oil of the lubricating crude oil contains a mineral oil and a synthetic ester, and the lubricating crude oil has a viscosity of 40 ° C.
By setting the temperature to 80 Cst. Or less at (normal temperature), the fluidity of the lubricant increases, and clogging does not occur in the pipes and nozzles of the lubricant supply device. Further, the lubricant is uniformly plated out on the roll surface, and a uniform lubrication state in the roll axis direction can be obtained.

Further, since the lubricating crude oil contains a mineral oil and a synthetic ester as a base oil, the lubricating properties of the mineral oil and the synthetic ester are significantly reduced when they come into contact with a high-temperature rolled material of 700 ° C. or more. The lubricant adhered to the rolled material biting portion does not hinder the biting of the rolled material. Further, the temperature of the roll cloth increases due to friction, and the oiliness is insufficient with mineral oil alone, but the lack of oiliness in the roll cloth is compensated for by containing 5% or more of synthetic ester, and the above-mentioned coefficient of friction is increased. Is secured.

In addition, by containing a fatty acid as an oiliness improver, the fatty acid reacts with iron on the roll surface to form a strong metal soap film, thereby preventing the oil film from breaking. Since the oil film does not break, the occurrence of roll vibration due to stick-slip is prevented. In addition, the fatty acid has an emulsifying action, and the lubricant is homogenized by the emulsifying action, so that the lubricant is uniformly applied in the axial direction of the roll surface,
A uniform lubrication state is obtained. However, the amount of fatty acid is 0.5
%, The coefficient of friction between the rolls increases due to the emulsifying action of the fatty acid. In addition, the amount of fatty acid is too small and 0.03
%, The coefficient of friction increases. Therefore, in order to secure the above range of the friction coefficient, the range of 0.03% to 0.5% is most appropriate as the amount of the fatty acid.

Further, the temperature between the work roll and the reinforcing roll is generally low temperature near normal temperature, but this portion may locally become 200 ° C. or higher due to friction generated by the roll cloth. The oil film forming action may be impaired. In the present invention, 0.1% of extreme pressure additive is added to lubricating crude oil.
By including the above, there is an effect of compensating for a portion where the action of the fatty acid is impaired, lowering the friction coefficient, and suppressing vibration.

Further, the fatty acid has an emulsifying action as described above, and if the fatty acid is too much, the separability from the coolant deteriorates. By setting the fatty acid content to 0.5% or less, the emulsification of the lubricant mixed in the coolant is suppressed and the separability is improved, and the oil content in the coolant is easily treated by the usual coagulant-separating agent treatment. Can be removed. This coolant is always circulated and used, and a part of it is constantly drained and replaced with fresh water. It is very important that the oil component in the agent can be easily separated and removed.

As described above, the fatty acid has the effect of emulsifying the oil component and achieving the uniformity of lubrication. However, in order to further enhance the effect, a surfactant may be mixed as an emulsifier, thereby reducing the roll surface. Lubrication can be performed more uniformly in the axial direction. On the other hand, as with the fatty acid, if the amount of the surfactant is too large, the friction coefficient between the rolls increases and the separability from the cooling agent deteriorates.
It is desirable to keep below.

Since the work roll is movable in the roll axis direction, it is possible to control the sheet crown both by controlling the cross angle of the work roll and by controlling the amount of movement in the axial direction. Further, schedule-free rolling can be performed by moving the work roll in the axial direction.

[0053]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, in the four-high rolling mill 10, a pair of upper and lower work rolls 2, 2 has a roll axis crossing the axis of the reinforcing rolls 3, and the upper and lower work rolls 2, 2. The roll axes intersect each other, and the sheet crown of the rolled material 1 is controlled by controlling the intersection angle of the upper and lower work rolls 2 to perform rolling. The work rolls 2 and 2 can be inclined with respect to the reinforcing rolls 3 and 3 in a horizontal plane such that their roll axes intersect each other by a configuration not shown.

The configuration in which the roll axes of the work rolls 2 and 2 cross each other is described in the above-mentioned Japanese Patent Application No. Hei.
No. 956 describes this in detail. In addition, the reinforcing rolls 3, 3 are usually configured so that the roll axis does not incline in the horizontal plane, but the roll axis inclines in the horizontal plane at 3 to 4 kinds of specific angles, and You may comprise so that it may not incline to an angle. Further, the reinforcing rolls 3, 3 are usually fixed so that their roll axes do not tilt freely in a horizontal plane during rolling, but may be tilted during rolling according to conditions.

Further, a cooling header 4 is provided at a position facing the work rolls 2 on the entry side and the exit side of the rolling mill 10, away from the contact position between the work roll 2 and the reinforcement roll 3 on the surface of the reinforcement roll 3. A lubricant supply device 5 is installed at the position, and is a first draining means so as to be in contact with the surface of the work roll 2 immediately before the contact position between the work roll 2 and the reinforcing roll 3 on the exit side of the rolling mill. The second draining plate 6 is brought into contact with the surface of the reinforcing roll 3 on the entry side of the rolling mill.
A draining plate 7 as a draining means is installed. still,
In the figure, the arrow A indicates the traveling direction of the rolled material, the arrow B indicates the flow direction of the coolant (hereinafter, referred to as cooling water), and the arrows C and D indicate the rotation directions of the reinforcing roll 3 and the work roll 4, respectively. In FIG. 1, the lubricant supply device 5 is schematically shown.

The cooling header 4 is supplied with cooling water sent from a cooling water tank 11 to a pipe 13 via a pump 12, and the cooling header 4 injects the cooling water, and 2 is cooled. After cooling the work roll 2, the temperature is raised, and the cooling water containing a large amount of scale and iron is
The water is collected in the pan 14 below the rolling mill together with the hot rolling oil, the inter-roll lubricant or the oil left from the equipment, and
Sent to 5. The treated water is sent by the pump 16 and is again stored in the cooling water tank 11 for circulating use. The water in the cooling water tank 11 is drained by a certain amount (for example, 50 m ³ / hr), and a corresponding amount of fresh water is supplied by a certain amount (for example, 50 m ³ / hr).

The lubricant supply device 5 includes a lubricant tank 21
Lubricant sent from the pump 22, the filter 23 and the pipe 24 is supplied, and the lubricant is injected from the lubricant supply device 5 onto the surface of the reinforcing roll 3. The position where the lubricant is injected is a position apart from the contact position between the work roll 2 and the reinforcement roll 3 on the surface of the reinforcement roll 3 as described above. Even if the cooling water accumulates between them, the distance is set such that the plate-out of the lubricant is performed firmly without being disturbed by the cooling water. Then, the lubricant plate-outed here is carried to the contact position between the work roll 2 and the reinforcing roll 3 with the rotation of the reinforcing roll 3, and lubrication between these rolls is performed.

As a lubricant, a mixed liquid of water and oil, that is, an emulsion liquid is often used, and the lubricating crude oil used for this lubricant is roughly classified into two types. One is a stable oil, which is called stable oil. It is mainly oil based on mineral oil and diluted with water to which emulsifier such as surfactant and fatty acid is added. The oil becomes water-soluble with the help of emulsifier. Water and oil do not separate even if left for a long time. The other one is unstable when it becomes an emulsion and is called unstable oil. It is based on beef tallow or mineral oil with an ester added, and the addition of emulsifiers such as surfactants and fatty acids is minimized. The oil is diluted with water. The oil has strong separation properties and is separated without mechanical mixing such as stirring. However, the lubrication performance is much larger than the former.

The former stable oil becomes a stable emulsion liquid and has a viscosity as low as 50 Cst. Or less, can be easily and uniformly plated out on the roll surface, and has good lubrication between rolls. In addition, the oil film of the stable oil adhered to the work rolls is burned off by the rolled material at a high temperature of 400 ° C. or higher during rolling, and the lubricating performance is reduced. good. However, when draining this water because it is water-soluble, it is necessary to forcibly separate the oil from the water by chemical treatment or the like. In general, the oil is separated using an acid such as H ₂ SO ₄ , neutralized using NaOH or the like, and then coagulated and precipitated. Therefore, expensive wastewater treatment equipment is required. Moreover, since the oil concentration is as high as 104 to 105 ppm, an ultrafilter for mechanically separating oil using a permeable membrane and an evaporator for evaporating and separating water are installed before the separation and coagulation by the above chemical treatment. It is necessary to perform a two-stage treatment of lowering the oil concentration to a lower concentration and then further performing a chemical treatment.

On the other hand, the latter unstable oil is difficult to become an emulsion liquid and is unstable. Therefore, in order to plate out uniformly and firmly on the roll surface,
It is necessary to use a low-viscosity base oil and spray it at an injection pressure of ² kg / cm ² or more to sufficiently plate out. However, the water film of the cooling water on the roll surface (water riding)
When water is present, it is necessary to break this water film and spray a lubricant in order to cause oil to adhere to the roll surface. Therefore, in this case, it is necessary to remove the water film on the roll surface in advance by a drain seal or the like, and spray the lubricant on the surface.

Once the oil adheres to the roll surface, its lubricating performance is far superior to the former stable oil. In addition, the biting property is good without using an additive such as hot rolling oil that does not impair lubrication at high temperatures. Further, since this emulsion liquid is easily separated, it does not require special treatment unlike stable oil even when mixed with cooling water. In particular, when converting a conventional four-high rolling mill to a work roll cross type rolling mill,
Since it is difficult to additionally install wastewater treatment equipment, it would be advantageous if the latter unstable oil could be used.

By the way, although it depends on the rotation speed of the roll and the injection pressure from the header, it is necessary to inject the lubricant many times as much as the amount to be applied in order to surely apply the lubricant to the roll surface. become. Even if excess lubricant not used for lubrication is directly poured into the cooling water treatment facility together with the roll cooling water, the amount of oil mixed into the circulating cooling water increases, and the work roll and reinforcement Although the original purpose of lubricating the contact part of the roll is achieved,
Large running costs will be incurred. For this reason, it is economical to recover and circulate an excess lubricant more than the amount required for lubrication, and this embodiment employs this method.

That is, the excess lubricant that has flowed down without adhering to the reinforcing roll 3 is collected by a header cover 42 (described later) constituting a part of the lubricant supply device 5 and returned to the lubricant tank 21. As the lubricant in the lubricant tank 21, a stable emulsion liquid obtained by diluting a stable oil having good emulsification stability with water with water or an unstable oil obtained by diluting an unstable oil having strong separability with water with water. Emulsion liquid is appropriately used depending on conditions. That is, in this embodiment, the lubricant is reliably plate-out on the roll surface regardless of whether the stable emulsion liquid or the unstable emulsion liquid is used.

The lubricant tank 21 is replenished with reduced water and lubricating crude oil, and is constantly stirred by the agitator 25 to maintain the emulsion property. At this time, the concentration of the lubricating crude oil is kept at, for example, 3%. The lubricant stored in the lubricant tank 21 is again pumped up by the pump 22, and impurities such as dust are removed by the filter 23, and the lubricant supply device 5
Injected from. As a result, the lubricant is not mixed into the circulating cooling water except for the one that is adhered to the roll and carried away. Not only the unstable emulsion having good separability, but also the emulsion stability is good and the separability is poor. Even when a stable emulsion liquid is used, there is no problem in the treatment of cooling water. Therefore, the treatment of the cooling water becomes easy. Further, lubrication can be performed with a minimum amount of lubricant necessary for inter-roll lubrication.

The lubricant adhering to the rolls and lubricating between the work rolls 2 and the reinforcing rolls 3 is collected together with the cooling water in the pan 14 below the rolling mill as described above.
To be processed. The lubricant tank 21, the pump 22, the filter 23, the pipe 24 and the agitator 25 constitute a lubricant circulation system.

At the outlet side of the rolling mill, cooling water injected from the cooling header 4 to the work roll 2 is supplied to the work roll 2.
If it enters the contact position between the roll and the reinforcing roll 3 or directly adheres to the reinforcing roll 3, the adhesiveness of the lubricant is deteriorated or the lubricant is washed away, so that the lubricity between the rolls is deteriorated. Further, at the entry side of the rolling mill, the cooling water sprayed on the work roll 2 and adhered to the surface thereof is formed as a water film and carried along with the rotation of the work roll and the reinforcing roll. When the lubricant is brought into the position where the lubricant is injected from the lubricant supply device 5, the plate-out of the lubricant is disturbed, and the lubricity between the rolls is also deteriorated. This is the same not only when the lubricating crude oil is the above-mentioned stable oil but also when the unstable oil is used.

On the other hand, the drain plate 6 shuts off the cooling water immediately before the contact position between the work roll 2 and the reinforcing roll 3 to prevent the cooling water from entering this portion as described above. The plate 7 removes a water film on the surface of the reinforcing roll 3 and prevents the cooling water from being brought into the position of the lubricant supply device 5 as described above. In this way, the draining plates 6 and 7 ensure that the plate-out of the lubricant is performed without being disturbed by the cooling water.

FIG. 2 shows the lubrication between rolls in a work roll cross type rolling mill disclosed in Japanese Patent Application No. 4-20956.
This will be described below. As shown in FIG. 2, a pair of upper and lower work rolls 10
2, 102, the roll axis of which is the upper and lower reinforcing rolls 103,
103, and the roll axes of the upper and lower work rolls 102, 102 intersect with each other,
By controlling the intersection angle between the upper and lower work rolls 102, 102, the sheet crown of the rolled material 100 is controlled, and rolling is performed. On the exit side of the rolling mill 101, a cooling header 10 is provided.
The cooling water supplied to the pipe 107 from the cooling water tank 105 via the pump 106 is provided in the header 1.
04, and cools the work rolls 102, 102. After cooling the work roll 102, the temperature of the cooling water is increased, and the cooling water containing a large amount of scale and iron is collected in a pan 108 below the rolling mill together with hot rolling oil, lubricant between rolls, or oil left from the equipment. It is watered and sent to a water treatment facility 109. The treated water is stored again in the cooling water tank 107 and used for circulation. The above configuration is similar to that of the present embodiment.

The header 110 is installed so as to face between the work roll 102 and the reinforcing roll 103, and the lubricant sent from the lubricant tank 111 to the pipeline 113 via the pump 112 is supplied from the header 110. Supplied,
Lubricant is supplied between the work roll 102 and the reinforcing roll 103 to provide lubricity. Further, a partition plate 114 may be provided between the header 104 and the header 110 so that cooling water does not enter between the work roll 102 and the reinforcing roll 103 and wash away the lubricant.

In this work roll cross type rolling mill 101, the inter-roll lubricant is directly injected from the header 110 installed between the work roll 102 and the reinforcing roll 103 to a position to be lubricated. The space between the work roll 102 and the reinforcing roll 103 is lubricated. However, in this case, the cooling water for cooling the work roll 102 from the header 104 becomes a water film and adheres to the work roll surface, and is carried between the work roll and the reinforcing roll with the rotation of the work roll, Cooling water accumulates in this portion, or mist-like cooling water injected from the header 104 directly accumulates in this portion, and even if the lubricant is injected more strongly from the header 110, the lubricant is applied between the work roll and the reinforcing roll. It is difficult to plate out well. This is shown in FIG.
Although it is moderately relaxed by the partition plate 114 as described above, it cannot be said that it is sufficient.

In particular, when the stable emulsion liquid is used as the lubricant between the rolls, the lubricant between the rolls easily dissolves in the cooling water accumulated between the work roll 102 and the reinforcing roll 103 and is washed away. The lubricating effect is almost lost. On the other hand, when an unstable emulsion liquid is used as the lubricant between the rolls, the lubricant between the rolls is not easily dissolved in the cooling water, but the lubricant cannot be plate-outed well because of the accumulated cooling water. .

On the other hand, in the present embodiment, as described above, the lubricant injection position is separated from the contact position between the rolls, and the header cover 42, the drain plates 6, 7 described later.
The lubrication between the work roll 2 and the reinforcing roll 3 can be reliably performed without being disturbed by the cooling water.

Next, the structure of the lubricant supply device will be described with reference to FIG.
And FIG. 3 and 4, the cooling water header 4 and the drain plates 6, 7 are omitted.
As shown in FIGS. 3 and 4, the lubricant supply device 5 is provided so as to be in contact with the work roll 3 on the exit side of the rolling mill, and a sliding guide 31 fixed to the rolling stand 17, a hydraulic cylinder 32, and a hydraulic cylinder 32. Piston 33 housed in
3 which is connected to the slide guide 31 and can slide on the slide guide 31
4. Frame 3 connected to frame 34 by pivot 35
4, a header block 36 slidable along with 4, a spring 37 for urging the header block 36 toward the reinforcing roll side, and a header 38 attached to the tip of the header block 36 and ejecting a lubricant as described above.

The lubricant supply device 5 is installed in a rolling mill as follows. That is, the header block 36, and thus the header 38, comes into contact with the surface of the reinforcing roll 3 from the outside of the mill window by the pressurized oil from a hydraulic source (not shown) in the hydraulic cylinder 32. Header 3
8 is installed by being pressed against the reinforcing roll 3. This installation position is variable, and the change in the diameter of the reinforcing roll 3 is adjusted by moving the position of the header block 36 in and out according to the change.

Next, the structure of the header 38 provided in the lubricant supply device 5 will be described with reference to FIG. Arrows E and F indicate the supply direction and the discharge direction of the lubricant, respectively. As shown in FIG. 5, the header 38 includes a lubrication nozzle 41 that injects a lubricant onto the surface of the reinforcement roll 3, a header cover 42 that surrounds the lubricant that is injected from the lubrication nozzle 41, and the reinforcement roll 3 of the header cover 42. It comprises a seal member 43 embedded in the facing end, and an oil drain pipe 44 serving as a lubricant discharge passage for discharging excess lubricant collected inside the header cover 42. The lubricant injected from the lubrication nozzle 41 and plate-out on the surface of the reinforcing roll is carried between the reinforcing roll 3 and the work roll 2 as described above, and the two rolls are lubricated. Excess lubricant scattered without adhering to the roll is collected by the header cover 42 and returned to the lubricant tank 21 (see FIG. 1) from the oil drain pipe 44.

The header cover 42 prevents the injected lubricant from scattering to the outside, and at the same time, prevents cooling water from entering from the outside. The sealing member 43 is made of a flexible material such as rubber, and is a contact-type sealing means that contacts the reinforcing roll 3.
The inside is sealed to prevent extra lubricant from leaking to the outside, and at the same time to prevent cooling water from entering from the outside.

The lubricating nozzle 41 is capable of injecting a lubricant at a pressure of 3 kg / cm ² or more. Therefore, even if a water film still exists on the roll surface due to the seal member 43 and the draining plates 6 and 7, the lubricant is sprayed from the lubrication nozzle 41 to spray the water film. The lubricant is pierced and the lubricant is reliably plated out on the roll surface. It is preferable that a plurality of lubrication nozzles 41 are provided in the header 38 and arranged so that adjacent lubricants overlap. Thereby, the lubricant can be uniformly attached to the roll surface.

According to the present embodiment as described above, the reinforcing roll 3 distant from the contact position between the work roll 2 and the reinforcing roll 3
Since the lubricant is supplied from the header 38 of the lubricant supply device 5 to a position on the surface, the lubricant is reliably lubricated between the work roll 2 and the reinforcing roll 3 without being disturbed by the cooling water. Can be. Therefore, the thrust force generated between the work roll 2 and the reinforcing roll 3 can be effectively reduced.

The header 38 has a header cover 42 surrounding the lubricant injected from the lubrication nozzle 41, an oil drain pipe 44 for discharging excess lubricant, and a sealing member 43 made of a flexible material such as rubber. Therefore, it is possible to prevent cooling water from being mixed into the injected lubricant and to prevent extra oil from scattering to the outside. In addition, drainer 6
And 7 are provided so as to be in contact with the surface of the reinforcing roll 3 on each of the exit side and the entrance side of the rolling mill, so that the plate-out of the lubricant is reliably performed without being obstructed by the cooling water.

Since the lubricant nozzle 41 injects the lubricant at a pressure of 3 kg / cm ² or more, the sealing member 43
Also, even if a water film still exists on the roll surface due to the draining plates 6 and 7, it is possible to pierce the water film and reliably plate out the lubricant on the roll surface.

Further, since the excess lubricant collected by the oil drain pipe 44 is collected in the lubricant tank 21 and supplied again to the lubricant supply device 5 for circulating use, the lubricant mixed in the cooling water is removed. The amount can be reduced, and the treatment of the cooling water mixed with the lubricant becomes easy. In addition, lubrication can be performed with a minimum necessary amount of lubricant without wasting the lubricant. Either stable oil or unstable oil may be used as the lubricating crude oil. Even when the stable oil is used, there is no problem in the treatment of the cooling water mixed with the lubricant.

Next, another embodiment of the present invention will be described with reference to FIG.
This will be described below. This embodiment is different from the above-described embodiment only in the configuration of the sealing means provided on the header for ejecting the lubricant. That is, as shown in FIG. 6, the sealing means of the present embodiment uses a high pressure supplied by gas supply means (not shown) from a slit 45 provided at an end of the header cover 42a of the header 38a facing the reinforcing roll 3. This is a non-contact type sealing means for injecting gas. That is, the high-pressure gas injected from the slit 45 flows in the direction of the arrow G in the drawing,
As in the case of the seal member 43 described above, the inside of the header cover 42a is sealed, so that excess lubricant is prevented from leaking outside, and at the same time, cooling water is prevented from entering from outside. Other effects are the same as those of the above-described embodiment.

Next, still another embodiment of the present invention will be described with reference to FIGS. This embodiment is an embodiment in which the taper is provided at both ends of the reinforcing roll 3 in the embodiment of FIGS. 1 to 5, and the shape of the sealing means of the header is changed accordingly. In FIGS. 7 and 8, the cooling water header and the drain plate are omitted.

During rolling, the roll surface may be subjected to Hertz deformation due to a rolling load and a roll bending force.
At this time, the axis between the reinforcing roll and the work roll approaches. In this case, since both end portions of the reinforcing roll are greatly deformed, the sealing means (the sealing member 43 in FIG. 3) of the header abutting on this portion may not function. This embodiment avoids this.

That is, as shown in FIGS. 7A and 7B, tapered portions 3c are provided at both ends of the reinforcing roll 3b.
As mentioned above, the roll surface is deformed by Hertz and the reinforcing roll 3b
The tapered portion 3c is prevented from contacting the surface of the work roll 2 even when the axis between the work roll 2 and the shaft approaches.
As shown in FIGS. 8A and 8B, the header 38 in the lubricant supply device 5b abutting on the tapered portion 3c.
The shape of the seal member 43b of b is a shape that comes into contact along the tapered portion 3c. With this configuration, in the above case, the tapered portion 3c does not contact the surface of the work roll 2 so that the tapered portion 3c is not deformed, and the sealing member 43b that is in contact with the tapered portion 3c functions as a sealing means. .

According to this embodiment as described above, not only the same effects as those of the embodiment described with reference to FIGS. 1 to 4 can be obtained, but also the roll surface is deformed in Hertz as described above and work with the reinforcing roll 3b is performed. The seal member 43b can perform its function even when the distance between the shaft and the roll 2 approaches.

Next, still another embodiment of the present invention will be described with reference to FIG. This embodiment is an embodiment of a rolling facility in which the rolling mill according to any of the above embodiments is installed. In FIG. 9, the draining plate is omitted. As shown in FIG. 9, the rolling equipment of the present embodiment includes the rolling mill 1
This is a row of hot finishing rolling mills that rolls rolled material 1 by arranging seven rolls 0 in a tandem rollable manner and sharing a system for supplying cooling water and a lubricant between the rolls of each rolling mill. Agent supply system 50 and roll cooling water supply system 60
Are installed respectively. That is, each reinforcing roll 3
Is provided with a lubricant supply device 51, a cooling water header 61 is provided on each work roll 2, and a pan 62 is provided at a lower portion of each rolling mill 10. A lubricant is circulated through the lubricant supply device 51. A lubricant tank 54 is connected via a pump 52 and a filter 53 to be used, and a water treatment facility 63 including a cooling water tank, a pump, and a water treatment device is connected to the cooling water header 61 and the pan 62. . The function of this rolling equipment is the same as that of the above-mentioned rolling mill, and the same effect can be obtained.

In this embodiment, all seven rolling mills are constituted by the work roll cross type rolling mills according to the above-mentioned embodiment, but at least one is constituted by the work roll cross type rolling mill according to the above-mentioned embodiment. Others may be constituted by conventional rolling mills.

Next, still another embodiment of the present invention will be described with reference to FIGS. However, in the following description, the same members as those in FIG. 1 are denoted by the same reference numerals.
As shown in FIG. 10, in the four-high rolling mill 10,
The pair of work rolls 2 and 2 have their roll axes crossing the axes of the reinforcing rolls 3 and 3 and the roll axes of the upper and lower work rolls 2 and 2 cross each other. By controlling the intersection angle of 2, the strip crown of the rolled material 1 is controlled, and rolling is performed. The work rolls 2 and 2 can be inclined with respect to the reinforcing rolls 3 and 3 in a horizontal plane such that their roll axes intersect each other by a configuration not shown.

The cooling header 4 is located at a position facing the work rolls 2 on the entry side and the exit side of the rolling mill 10 away from the contact position between the work roll 2 and the reinforcement roll 3 on the surface of the reinforcement roll 3. A lubricating header 5a is installed at the position, and furthermore, a draining means as first draining means is brought into contact with the surface of the work roll 2 immediately before the contact position between the work roll 2 and the reinforcing roll 3 on the exit side of the rolling mill. The second plate 6 is set so that the plate 6 contacts the surface of the reinforcing roll 3 on the entry side of the rolling mill.
A draining plate 7 as a draining means is installed. still,
In the figure, arrow A indicates the traveling direction of the rolled material, arrow B indicates the flow direction of the cooling water, and arrows C and D indicate the rotation directions of the reinforcing roll 3 and the work roll 4, respectively.

The cooling header 4 is supplied with cooling water sent from a cooling water tank 11 to a pipe 13 via a pump 12, and the cooling header 4 injects the cooling water to form the work rolls 2. 2 is cooled. After cooling the work roll 2, the temperature is raised, and the cooling water containing a large amount of scale and iron is
The water is collected in the pan 14 below the rolling mill together with the hot rolling oil, the inter-roll lubricant or the oil left from the equipment, and
Sent to 5. The treated water is sent by the pump 16 and is again stored in the cooling water tank 11 for circulating use. Further, the water in the cooling water tank 11 is drained by a certain amount (for example, 50 m ³ / hr), and a corresponding amount of fresh water is replenished by a certain amount (for example, 50 m ³ / hr).

The lubrication header 5a includes a lubricant tank 21
The lubricant is further pumped up by the pump 22, impurities such as dust are removed by the filter 23, and the lubricant sent through the pipe 24 is supplied. Then, this lubricant is sprayed onto the surface of the reinforcing roll 3 from the lubrication header 5a. The position at which the lubricant is sprayed is a position on the surface of the reinforcing roll 3 that is apart from the contact position between the work roll 2 and the reinforcing roll 3, and is substantially the same as the position where the lubricant supply device 5 of FIG. 1 is installed. Position. Then, the lubricant plate-outed here is carried to the contact position between the work roll 2 and the reinforcing roll 3 with the rotation of the reinforcing roll 3, and lubrication between these rolls is performed.

The position where the lubricant is sprayed is determined by the work roll 2 and the reinforcing roll 3 on the surface of the reinforcing roll 3 as described above.
This position is far from the contact position with the cooling roll, and even if cooling water is accumulated between the work roll 2 and the reinforcing roll 3, the plate-out of the lubricant is firmly performed without being disturbed by the cooling water. It is installed at a distance as would be done. Then, the lubricated plate-out is applied to the reinforcing roll 3
Is carried to the contact position between the work roll 2 and the reinforcing roll 3 with the rotation of, and lubrication between these rolls is performed.

Also, in this case, since the lubrication pad 5a does not have the header cover 42 as shown in FIG. 1, most of the lubricant after lubricating between the rolls is disposed under the rolling mill as described above. Is collected together with the cooling water in a pan 14 and sent to a water treatment device 15 for treatment. However, since the lubricating crude oil used in the present embodiment has a good separability from water as described later, the cooling water can be easily treated with a coagulation / separation agent which is usually used.

In the lubricant tank 21, lubricating crude oil and water described below are prepared at an appropriate concentration, for example, a concentration of 3%, and are constantly stirred by the agitator 25 to maintain the emulsion property. Further, the lubricant tank 21 is replenished with water or lubricating crude oil reduced by the inter-roll lubrication.

Next, the lubricant used in this embodiment will be described in detail. First, the results obtained by the inventors of the present application examining the conditions for putting the working roll cross-type rolling mill according to the present embodiment into practical use are summarized as follows. (1) Coefficient of friction between rolls (1)-(a) The coefficient of friction is 0.1 or less due to the limitation of the load capacity of the thrust bearing of the work roll. 5% is the maximum. In the work roll cross type rolling mill, the thrust force applied to the work roll is the difference between the force from the reinforcing roll (corresponding to the above-mentioned friction coefficient of 0.1) and the force from the rolled material (up to 5% of the rolling load). Therefore, if the coefficient of friction between the rolls is 0.1 or less, the thrust load applied to the work rolls is 5% or less of the rolling load.

(1)-(b) The friction coefficient is 0.04 or more so that the reinforcing roll does not slip at the time of acceleration after the rolled material bites and at the time of deceleration after the trailing edge has fallen. Since the roller is driven by the work roll, if the friction coefficient between the rolls is small, slip occurs, and the surface of the reinforcing roll is locally worn. Normally, a relatively large force corresponding to the balance force of the work roll is applied to the reinforcing roll, but even in this case, the resistance of the seal of the reinforcing roll bearing (corresponding to a friction coefficient of about 0.01) and acceleration are required. In order to transmit an inertia torque (corresponding to a friction coefficient of 0.02 to 0.03) and the like, the friction coefficient between rolls needs to be 0.04 or more.

(2) Engaging property of rolled material At high temperatures, the lubrication performance of the lubricant is remarkably deteriorated. Biting will be hindered. However, since the lubricant comes in contact with the rolled material having a high temperature of 700 ° C. or higher, it is essential to use lubricity in which the lubricity disappears at a high temperature for practical use of a work roll cloth type rolling mill. Condition.

(3) Vibration caused by slip speed due to cross between rolls (3)-(a) It is desirable that the friction coefficient between rolls is smaller in order to prevent the occurrence of vibration of rolls. Is a stick-slip which uses elastic deformation of the roll surface in the axial direction as a spring, and does not occur when the friction coefficient is small (usually 0.1 or less).

(3)-(b) In order to prevent the vibration of the rolls, it is preferable that the oil film strength of the lubricant is large. The load acting between the rolls is very large. Boundary lubrication occurs, and the above-mentioned stick slip occurs when the lubricating oil film is broken. Therefore, to prevent this vibration, it is important to increase the oil film strength.

(4) Uniform lubrication of the roll surface in the axial direction The viscosity of the lubricant should be 80 Cst. Or less at 40 ° C. (normal temperature). The smaller the viscosity, the better the fluidity and the clogging in the lubricant supply device. Is applied uniformly on the roll surface, and a uniform lubrication state is obtained.

(5) Treatment of Cooling Water Containing Lubricants Lubricant mixed in cooling water has good separability, and the lubricant lubricated between the rolls inevitably requires a large amount of cooling for the work rolls. Mix in cooling water. The cooling water is constantly circulated and is always replaced with fresh water, and the amount is constantly discharged outside the factory. Therefore, it is very important that the separation of the cooling water mixed with the lubricant is easy. Conversely, if the separability is poor, enormous costs are required for this processing, or this processing apparatus becomes large-scale, and it becomes impossible to practically realize a work roll cross type rolling mill.

The conditions for the practical use of the above work roll cross type rolling mill are as follows, as the lubricating oil of the lubricant,
(A) The coefficient of friction between the work roll and the reinforcing roll is 0.
(B) the viscosity is 40 ° C.
(C) containing mineral oil and 5% or more synthetic ester as a base oil, (d) containing 0.03-0.5% of a fatty acid as an oiliness improver,
It has been found that this can be achieved by using a material that satisfies (e) 0.1% or more of an extreme pressure additive and (f) 0.5% or less of a surfactant as an emulsifier that can be contained. did. Hereinafter, this will be described in relation to conditions for practical use.

(1) Coefficient of friction between rolls The coefficient of friction between rolls is (a) based on the load capacity of the work roll in (1)-(a) and the restriction of slip prevention of the reinforcing roll in (1)-(b). ) Must be in the range of “0.04 to 0.1”.

The upper limit of the inter-roll friction coefficient is shown in FIG.
1 will be described. In Figure 11, f _B is a thrust coefficient representing the thrust force that the work roll receives from the rolls corresponds to the roll between the coefficient of friction. F _WS is a thrust coefficient representing the thrust force received by the work roll from the rolled material, and f _W is a thrust coefficient representing the total thrust force received by the work roll. However, FIG. 11 shows an example in which the inter-roll friction coefficient is 0.05.

As described above, the work roll 2 having a small load capacity is provided with the thrust force received from the reinforcing roll 3 and the rolled material 1.
And the thrust force received from the
Since the directions of these forces are opposite, the thrust force received by the work roll 2 is the difference between the two forces as shown in FIG. That is, f _W is the difference between f _B and f _WS . However, the thrust force that the work roll 2 receives from the rolled material 1 is at most 5 even when the rolled material 1 receives the maximum rolling load.
Therefore, in order to reduce the thrust force received by the work roll 2 to 5% or less of the rolling load as described above, the thrust force received by the work roll 2 from the reinforcing roll 3 is set to 10% or less of the rolling load. It will be good. That is, the coefficient of friction between rolls may be 0.1 or less.

Next, the lower limit of the inter-roll friction coefficient will be described. When the friction between the rolls is small, the rotation of the reinforcing rolls cannot follow the rotation of the work roll 2 and slips at the time of acceleration after the rolled material bites and at the time of deceleration after the rolled material comes off, and the surface of the reinforcing rolls slips. Will be locally worn. In particular, this slip is likely to occur at the time of deceleration after the rolled material comes off the tail. The coefficient of friction between the rolls required when the rolls are accelerated / decelerated is expressed by the following equation.

[0108]

(Equation 1)

Here, μ _r is the resistance of the seal of the bearing of the reinforcing roll, I is the moment of inertia of the reinforcing roll, ω is the rotational angular velocity of the reinforcing roll, and Q is the work roll 2 and the reinforcing roll 3.
Power (50ton or more can be secured with the actual machine), R _B
Is the radius of the reinforcing roll 3. In the formula (1), mu _r is the first term of the left side corresponds to 0.01 of the friction coefficient, the second term is a inertial torque required for acceleration, 0.02 the friction coefficient is calculated for actual 0.03.
Therefore, the lower limit of the inter-roll friction coefficient may be 0.04.

(2) Biting property of rolled material Biting property of rolled material is achieved by including mineral oil and 5% or more synthetic ester as base oil of (c). Mineral oils and synthetic esters are different from animal and vegetable oils.
This is because the lubricating property is significantly reduced by the high temperature of the rolled material. That is, the lubricant adhering to the work roll surface is carried to the rolled material biting portion and comes into contact with the rolled material having a high temperature of 700 ° C. or more. At this time, the mineral oil and the synthetic ester are burnt off at the high temperature and the lubricity thereof is significantly reduced. Therefore, it does not hinder the biting of the rolled material.

The temperature of the roll cloth rises due to wear, and the oiliness of mineral oil alone is insufficient. 5% as base oil
By including the above synthetic ester, the shortage of oiliness in the roll cloth portion is compensated, and the above-mentioned friction coefficient is secured.

(3) Vibration attributable to slip speed due to inter-roll cloth Regarding generation of roll vibration, (a) low friction coefficient between rolls and (c) 5% or more of synthetic ester contained , (D) a fatty acid as an oil improver in an amount of 0.03
The vibration can be prevented by containing 0.5% to 0.5% and (e) containing 0.1% or more of the extreme pressure additive. Hereinafter, this will be described.

In the experimental results showing the vibration generation limit as shown in FIG. 12, if the friction coefficient between the rolls becomes small, no vibration occurs, and no vibration due to the crossing of the work roll 2 occurs. Note that FIG.
In this case, a lubricant containing 5% of a lubricating crude oil is used. The vibration generation limit varies depending on the oil film strength of the lubricant. If a lubricant made of a lubricating oil containing no fatty acid is used, vibration is generated even when the friction coefficient between rolls is even smaller.

Further, by containing a fatty acid as an oiliness improver, the fatty acid reacts with iron on the roll surface to form a strong metal soap film, thereby preventing the oil film from breaking. Since the oil film does not break, the occurrence of roll vibration due to stick-slip is prevented.

When the amount of the fatty acid exceeds 0.5%, the friction coefficient between the rolls increases due to the emulsifying action of the fatty acid.
Further, even if the amount of the fatty acid is too small and 0.03% or less, the coefficient of friction increases. Therefore, in order to secure the above-mentioned appropriate friction coefficient range, the amount of the fatty acid is 0.03%
The range of .about.0.5% is most appropriate.

Although the temperature between the work roll and the reinforcing roll is generally low near normal temperature, the temperature may be locally higher than 200 ° C. due to friction generated by the roll cloth.
The action of the above fatty acids, that is, the action of increasing the oil film strength and eliminating the vibration of the roll, may be impaired. On the other hand, extreme pressure additives have lubricating properties even at 200 ° C. or higher.
By adding about%, the portion where the action of the fatty acid is impaired is supplemented to lower the friction coefficient, thereby contributing to prevention of roll vibration.

(4) Uniform lubrication of the roll surface in the axial direction Regarding this uniform lubrication, (b) a viscosity of 40 C. and 80 Cs
t. or less, (c) including a mineral oil and a synthetic ester as a base oil, (d) including a fatty acid, and (f) including a surfactant. Hereinafter, this will be described.

[0118] Oils currently used as hot rolling oils include animal and vegetable oils (oils and fats) having lubricity even at high temperatures, and these oils have a viscosity of about 1 at 40 ° C (normal temperature).
It is as high as 00 Cst. Or more and has very poor fluidity. Therefore, the lubricant tank and the supply pipe are heated and supplied with steam to improve the fluidity. However, clogging often occurs in the pipe and the like, and the fluidity is poor even on the roll surface. And the trouble of poor lubrication has occurred.
As a result of an experiment conducted on the conditions for securing the fluidity, it was found that mineral oil and synthetic ester were used as the base oil, and the temperature was 40 ° C.
If the viscosity at room temperature was 80 Cst. Or less, it was confirmed that the above-mentioned trouble did not occur.

The fatty acid (d) has an emulsifying action,
As the lubricant is homogenized by this emulsifying action, the lubricant is also applied uniformly in the axial direction of the roll surface,
A uniform lubrication state is obtained. Further, by adding a surfactant as an emulsifier, the uniformity of lubrication is further enhanced, and the roll surface can be more uniformly lubricated in the axial direction.

As for the fatty acid (d), as described above, in order to secure the above-mentioned appropriate range of the friction coefficient, the amount of the fatty acid is most preferably in the range of 0.03% to 0.5%. It is. Also, as with the fatty acid, if the amount of the surfactant is too large, the coefficient of friction between the rolls increases. Therefore, the amount of the surfactant is preferably limited to 0.5% or less as in the case of the fatty acid.

(5) Treatment of Cooling Water Containing Lubricants In the above (5), the fatty acid in (d) should be 0.5% or less, and the surfactant in (f) should be 0.5% This can be achieved by:

As described above, fatty acids have an emulsifying effect, and if the amount is too large, the separability from a cooling agent is deteriorated. By setting the fatty acid content to 0.5% or less, the emulsification of the lubricant mixed in the coolant is suppressed and the separability is improved, and the oil component in the coolant is easily treated by the usual coagulant-separating agent treatment. Can be removed. The same applies to surfactants,
It is desirable that this amount be kept to 0.5% or less as in the case of fatty acids. In other words, fatty acids and surfactants are advantageous for producing a uniform emulsion solution, but if added in excess, the separability of the lubricant mixed in the cooling water is deteriorated.
Limit to 0.5% or less.

Next, an example of the lubricant used in the experiment in this embodiment will be described. In the present embodiment, the following lubricating crude oil was used in consideration of the above-described examination results. Base oil: 82% mineral oil (paraffinic) and 15% synthetic ester Fatty acid (oleic acid): 0.5% Extreme pressure additive: 1.0% Surfactant (emulsifier): none Other (for example, antioxidant): 1.5% or more of lubricating crude oil is mixed with water and supplied as a 3% emulsion, and hot-rolled material having a temperature of 900 ° C or more is crossed at a work roll cross angle of 0.5 ° to 1.5 ° Rolled. The results obtained are as follows. Roll friction coefficient: 0.045 to 0.07 Biting friction coefficient: 0.2 or more Roll vibration: Rolling load (linear pressure between rolls) 2 ton
In the above, the bite friction coefficient is a friction coefficient at the time of biting of the leading end of the rolled material, and was calculated by the following equation.

[0124]

(Equation 2)

Here, μ _b is the bite friction coefficient, R is the radius (mm) of the work roll 2, ΔH is the rolling reduction (mm), P is the rolling load (ton), K is the mill rigidity (ton / Mm).

Therefore, according to the present embodiment, it is possible to secure the biting ability of the rolled material while reducing the thrust force between the rolls, and also to prevent the occurrence of roll vibration, so that a stable operation of the work roll cloth rolling mill can be achieved. It becomes possible. Further, the treatment of the cooling water mixed with the lubricant becomes easy. Further, since the treatment of the cooling water is easy, there is an effect that it is easy not only to newly install a work roll cross rolling mill but also to easily convert an existing rolling mill to a work roll cross type rolling mill.

Next, still another embodiment of the present invention will be described with reference to FIG. In this embodiment, the lubricating oil is directly supplied to the surface of the reinforcing roll 3 instead of mixing the lubricating oil with water to form an emulsion. In FIG. 14, lubricating crude oil stored in a lubricant tank 90 is pumped up by a pump 91, impurities such as dirt are removed by a filter 92, and injected from a lubrication header 5 a through a pipe 93. The lubricant tank 90 is replenished with the lubricating oil reduced by the inter-roll lubrication. However, the other configuration and the conditions that the lubricating crude oil satisfies are the same as those in the embodiment of FIG. 10, and the same reference numerals are given to members equivalent to those in FIG.

According to this embodiment as described above, not only the same effects as in the embodiment described with reference to FIGS. 10 to 13 can be obtained, but also because the lubricating crude oil is directly used as the lubricant, The supply amount of the lubricant supplied to the header 5a may be significantly smaller than that in the case of supplying the emulsion liquid.

Next, still another embodiment of the present invention will be described with reference to FIG. In the present embodiment, lubricating crude oil is mixed with compressed air and injected onto the surface of the reinforcing roll 3. In FIG. 15, the lubricating oil stored in the lubricant tank 94 is pumped up by a pump 95, and impurities such as dust are removed by a filter 96 and sent to a mixer 97. Compressed air is sent to the mixer 97, where the lubricating crude oil and the compressed air are mixed. Then, the lubricating crude oil mixed with the compressed air is sent to the lubrication header 5a through the pipe 98, and is injected from the lubrication header 5a. The lubricant tank 94 is replenished with the lubricating oil reduced by the inter-roll lubrication. However, the other configuration and the conditions that the lubricating crude oil satisfies are the same as those in the embodiment of FIG. 10, and the same reference numerals are given to members equivalent to those in FIG.

According to this embodiment as described above, not only the same effects as in the embodiment described with reference to FIG. 14 can be obtained, but also the lubricating crude oil is injected using compressed air, so that the lubricating oil exists on the roll surface. Through the water film, the lubricating crude oil can be reliably plate-out on the surface of the reinforcing roll 3.

Next, an embodiment in which the inclination of the work rolls is controlled and the amount of movement of these work rolls in the roll axis direction is controlled to control the strip crown of the rolled material will be described with reference to FIG.

In FIG. 16, a work roll chock 70 is provided at each roll end of the upper and lower work rolls 2 and rotatably supports the upper and lower work rolls 2. The work roll chock 70 is disposed facing a window surface 71a of a pair of stands 71 that are vertically separated from each other in the roll axis direction of the rolling mill.

In order for the roll axes of the upper and lower work rolls 2 to intersect with the roll axes of the upper and lower reinforcement rolls 3 and the roll axes of the upper and lower work rolls 2 to intersect each other, the project block 7 of the stand 71 is used.
2 is provided with hydraulic jacks 73 and 74, respectively. That is, by operating both of the hydraulic jacks 73 and 74, the work roll chock 70 is inclined, and the upper and lower work rolls 2 can be crossed.

The hydraulic jack 73 is supplied with pressurized oil via a switching valve 75, and the amount of movement of the hydraulic ram of the hydraulic jack 73 depends on the amount of displacement of a rod 76 attached to the hydraulic ram. It is detected by the sensor 77. Then, the switching valve 75 is adjusted by the work roll cross angle controller 78 based on a signal corresponding to the rolling conditions to drive the hydraulic jack 73, and feedback control is performed by a signal from the sensor 77 to set the desired vertical cross angle. Control. Also, the hydraulic jack 74
Is supplied with pressure oil via a pressure reducing valve 79, and presses the work roll chock 70 with a necessary pressing force. The change of the cross angle can be performed during rolling, that is, even when a large rolling load is applied.

The stand 71 is provided with two hydraulic cylinders 80 driven along the work roll axis so that the upper and lower work rolls 2 can move in the roll axis direction. 70 are sandwiched therebetween. The hydraulic cylinder 80 is always filled with oil by a pilot check valve 81 so that its position can be maintained. The rods of the two hydraulic cylinders 80 are connected to a common moving block 82, and a detachable locking portion 82 a provided on the moving block 82 is engaged with a projecting portion 70 a formed at an end of the work roll chock 70. The driving force of the hydraulic cylinder 80 is transmitted to the work roll chock 70 so that the upper and lower work rolls 2 can be moved in the roll axis direction. However, although illustration is omitted, it goes without saying that the control of the operation of moving the upper and lower work rolls 2 in the axial direction is also controlled by the movement amount control device according to the rolling conditions.

The mechanism of this embodiment is applicable to all the embodiments described above. Thus, the upper and lower work rolls 2
Since it is possible to move not only in the cross direction but also in the roll axis direction, it is possible to control both the inclination angle and the axial movement amount of the work roll to control the sheet crown.
Further, since the work roll can be moved in the axial direction, schedule-free rolling can be performed.

[0137]

According to the present invention, the lubricant is supplied from the lubricant supply device to a position on the surface of the reinforcing roll remote from the contact position between the work roll and the reinforcing roll, so that the lubricant is reliably prevented from being obstructed by the coolant. In addition, lubrication between the work roll and the reinforcing roll can be performed. Therefore, the thrust force generated between the rolls can be effectively reduced.

Further, since the lubricant injected from the lubrication nozzle is surrounded by the cover, it is possible to prevent the coolant from being mixed with the injected lubricant, and to prevent the excess lubricant from scattering outside. In addition, since the sealing means is provided at the end of the cover, the inside of the cover is sealed, so that the mixing of the coolant into the lubricant and the scattering of the lubricant to the outside can be prevented. Furthermore, since the draining means is provided, the plate-out of the lubricant is reliably performed without being obstructed by the coolant.

Further, since the lubricant is sprayed from the lubrication nozzle in the form of a spray, even if a water film exists on the roll surface, the lubricant can be broken out and the lubricant can be plated out.

Further, since taper portions are provided at both ends of the reinforcing roll and the sealing means is formed so as to be in contact therewith, the surface of the roll is deformed by Hertz, so that the shaft between the reinforcing roll and the work roll approaches each other. The sealing means also fulfills its function.

Further, since the collected excess lubricant is circulated, the amount of lubricant mixed in the cooling water can be reduced, and the treatment of the cooling water becomes easy. In addition, lubrication can be performed with a minimum necessary amount of lubricant without wasting the lubricant. Either stable oil or unstable oil can be used as the lubricating crude oil for the lubricant.

Further, since the coefficient of friction between the rolls is in the range of 0.04 to 0.1, the thrust force applied to the work rolls can be made to be equal to or less than the allowable force of the ordinary work rolls. It is possible to prevent the reinforcing roll from slipping at the time of acceleration after intrusion or at the time of deceleration after slippage. Also,
This condition also has the effect of preventing the roll from vibrating.

The viscosity of the lubricating crude oil was 80 Cst.
Since the fluidity of the lubricant is increased, clogging does not occur in the piping and nozzles of the lubricant supply device, and the lubricant is evenly plated out on the roll surface to obtain a uniform lubrication state.

In addition, since mineral oil is contained as the base oil of the lubricating crude oil, the lubricant does not hinder the biting of the rolled material. In addition, since it contains 5% or more of synthetic ester, it is possible to make up for the lack of oiliness of the mineral oil due to the temperature rise.

Further, as an oiliness improver, a fatty acid is used in an amount of 0.03.
% Or more, it is possible to prevent the oil film from running out and to prevent the roll from vibrating due to stick-slip. Furthermore, since the fatty acid content is 0.5% or less, an increase in the friction coefficient between the rolls due to the emulsifying action of the fatty acid can be suppressed.

Further, since the lubricating crude oil contains 0.1% or more of the extreme pressure additive, the portion where the action of the fatty acid is impaired can be compensated.

Further, since the amount of the surfactant or emulsifier which can be contained in the lubricating crude oil is set to 0.5% or less, the emulsification of the lubricant mixed in the coolant is suppressed and the separability is improved.
The oil component in the coolant can be easily removed by the coagulation / separation agent treatment which is usually simply performed.

Further, since the work roll can be moved in the roll axis direction, the sheet crown control can be performed by controlling both the cross angle of the work roll and the amount of movement in the axial direction. Further, schedule-free rolling can be performed by moving the work roll in the axial direction.

[Brief description of the drawings]

FIG. 1 is a view showing a rolling mill and a rolling method according to an embodiment of the present invention.

FIG. 2 is a diagram showing a system for supplying a lubricant between rolls and a coolant in a work roll cross type rolling mill disclosed in Japanese Patent Application No. 4-20956.

FIG. 3 is a diagram illustrating a configuration of a lubricant supply device installed in the rolling mill of FIG. 1;

FIG. 4 is an arrow view from the IV-IV direction in FIG. 3;

FIG. 5 is a cross-sectional view showing a configuration of a header provided in the lubricant supply device of FIG.

FIG. 6 is a view showing another embodiment of the present invention, and is a cross-sectional view showing a configuration of a header provided in a lubricant supply device.

FIG. 7 is a view showing still another embodiment of the present invention,
(A) is a figure which shows the structure of the rolling mill and the lubricant supply apparatus installed in a rolling mill, (b) is the arrow view from the B direction of (a).

8 (a) is a view taken in the direction of arrows VIII-VIII in FIG. 7 (a), and FIG. 8 (b) is a partial view taken in the direction of arrows VIII-B in FIG. 7 (a).

FIG. 9 is a view showing still another embodiment of the present invention,
It is a figure which shows the rolling equipment which installed the rolling mill of this invention.

FIG. 10 is a view showing still another embodiment of the rolling mill and the rolling method according to the present invention.

FIG. 11 shows a thrust force generated when the cross angle of the work roll is changed, expressed by a thrust coefficient.

FIG. 12 is an experimental result showing a vibration generation limit when a friction coefficient between rolls and a linear pressure between rolls (that is, rolling load) are changed.

FIG. 13 is a graph showing the relationship between the fatty acid concentration and the roll friction coefficient in a lubricant having a 2% emulsion liquid concentration.

FIG. 14 is a view showing still another embodiment of the rolling mill and the rolling method according to the present invention.

FIG. 15 is a view showing still another embodiment of the rolling mill and the rolling method according to the present invention.

FIG. 16 is a view illustrating still another embodiment of the present invention including a mechanism for crossing a work roll and a mechanism for moving the work roll in the roll axis direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolled material 2 Work roll 3 Reinforcement roll 3b Reinforcement roll 3c Taper part 4 Cooling header 5 Lubricating oil supply device 5a Lubricating header 5b Lubricating oil supply device 6,7 Drain plate 10 Rolling machine 15 Water treatment device 21 Lubricating oil tank 22 Pump 23 Filter 24 Pipeline 25 Agitator 31 Sliding guide 32 Hydraulic cylinder 33 Piston 34 Frame 36 Header block 37 Spring 38, 38a, 38b Header 41 Lubrication nozzle 42, 42a Header cover 43, 43b Seal member 44 Oil drain pipe 45 Slit 50 Lubricating oil supply system between rolls 51 Lubricating oil supply device 52 Pump 53 Filter 54 Lubricating oil tank 60 Roll cooling water supply system 61 Cooling water header 62 Pan 63 Water treatment system 73, 74 Hydraulic jack 75 Switching valve 76 Rod 7 7 Sensor 78 Work roll cross angle controller 79 Pressure reducing valve 80 Hydraulic cylinder 81 Pilot check valve 82 Moving block 90 Lubricant tank 91 Pump 92 Filter 93 Pipeline 94 Lubricant tank 95 Pump 96 Filter 97 Mixer 98 Pipeline

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI B21B 37/28 B21B 45/02 310 45/02 310 37/00 116J (72) Inventor Takao Sakanaka Sankomachi, Hitachi-shi, Ibaraki Hitachi 1-1, Hitachi Ltd. (72) Inventor Shinichi Yasunari 3-1-1 Sakaimachi, Hitachi, Ibaraki Pref. Hitachi, Ltd. Hitachi Plant (72) Yoshio Takakura Hitachi, Hitachi, Ibaraki Hitachi 1-1, Sachimachi Co., Ltd.Hitachi Plant, Hitachi, Ltd. (72) Inventor Shinichi Kaga 3-1-1, Sachimachi, Hitachi, Ibaraki Pref. Hitachi, Ltd.Hitachi Plant (56) References JP5 JP-A-285504 (JP, A) JP-A-6-31315 (JP, A) JP-A-6-15314 (JP, A) JP-A-5-277521 (JP, A) JP-A-5-50110 (JP, A) ) Special Flat 5-200417 (JP, A) JP Akira 59-39409 (JP, A) JP Akira 57-4314 (JP, A) (58 ) investigated the field (Int.Cl. ^6, DB name) B21B 27 / 10 B21B 1/22 B21B 13/14 B21B 37/28 B21B 45/02 310

Claims (22)

(57) [Claims] 1. A pair of work rolls, a pair of reinforcing rolls respectively supporting the work rolls, and a cooling means for cooling a pair of work rolls by injecting a coolant from the outgoing side or the incoming side of the rolling mill. The pair of work rolls are arranged to be inclined in a horizontal plane such that their axes intersect with the axes of the pair of reinforcing rolls, respectively, and the axes of the work rolls intersect with each other. In a work roll cross-type rolling mill, each of the pair of reinforcing rolls is disposed so as to face each other,
Lubricant that injects lubricant at a position on the surface of the reinforcing roll remote from the respective contact positions between the pair of work rolls and the pair of reinforcing rolls to lubricate between the respective work rolls and the reinforcing roll A work roll cross type rolling mill comprising a supply device. 2. The lubricant supply device according to claim 1, wherein each of the lubricant supply devices includes a lubrication nozzle that injects a lubricant to a position on the surface of the reinforcing roll, and a lubricant nozzle that surrounds the lubricant injected from the lubrication nozzle. A cover for collecting excess lubricant, sealing means provided at an end of the cover facing the reinforcing roll to seal the inside of the cover, and lubrication for discharging excess lubricant collected inside the cover The work roll cross type rolling mill according to claim 1, further comprising an agent discharge passage. 3. The work roll cloth rolling mill according to claim 2, wherein said sealing means includes a flexible material that comes into contact with said reinforcing roll. 4. The work roll cross type rolling mill according to claim 2, wherein said sealing means includes a slit for injecting high pressure gas into said reinforcing roll. 5. The work roll, at the outlet side of the rolling mill, being in contact with the surface of the work roll immediately before a contact position between the work roll and the reinforcing roll when viewed in the respective rotation directions of the pair of work rolls. 2. A work roll cloth type rolling mill according to claim 1, further comprising a first draining means disposed in the work roll and blocking the coolant so that the coolant injected into the work roll does not enter the contact position. 6. The work roll and the reinforcing roll are arranged so as to be in contact with the surfaces of the pair of reinforcing rolls, respectively, sprayed onto the pair of work rolls, adhered to the surfaces, and carried with the rotation of the work roll and the reinforcing roll. The work roll cloth type rolling mill according to claim 1, further comprising a second drainer for removing the coolant so that the coolant is not brought into a position where the lubricant supply device is disposed. 7. The lubricant supplied from the lubricant supply device is based on a mineral oil to which an ester is added, and is based on a lubricating crude oil in which addition of a surfactant and a fatty acid for improving emulsifiability is reduced as much as possible. The work roll cross type rolling mill according to claim 1, further comprising: 8. The lubricant supplied from the lubricant supply device has the following conditions: (a) The friction coefficient between the work roll and the reinforcing roll is in a range of 0.04 to 0.1. (B) a viscosity of 80 Cst. Or less at 40 ° C., (c) a mineral oil and 5% or more synthetic ester as a base oil, and (d) a fatty acid as an oiliness improver of 0.03-0.5. The working roll cloth type rolling mill according to claim 1, further comprising: a lubricating crude oil that satisfies (e) an extreme pressure additive of 0.1% or more. 9. The work roll cloth rolling mill according to claim 8, wherein the lubricating crude oil further contains (f) a surfactant as an emulsifier in an amount of 0.5% or less. 10. The work roll cloth type according to claim 7, wherein the lubricant supplied from the lubricant supply device is a highly separable emulsion liquid obtained by diluting the lubricating crude oil with water. Rolling mill. 11. The work according to claim 1, wherein the lubricant supplied from the lubricant supply device includes a lubricating crude oil based on mineral oil to which a surfactant or a fatty acid is added to improve the emulsifiability. Roll cross type rolling mill. 12. The work roll cloth type rolling according to claim 1, wherein the lubricant supplied from the lubricant supply device is an emulsion liquid having good emulsion stability obtained by diluting the lubricating crude oil with water. Machine. 13. A roll surface of the pair of reinforcing rolls is deformed by Hertz due to a rolling load and a roll bending force at both ends thereof, and the axis of the reinforcing roll and the axis of a work roll supported by the reinforcing roll are aligned with each other. 4. A tapered portion which does not come into contact with the work roll even when approached, and a portion of the sealing means facing the tapered portion is shaped to contact along the tapered portion. Work roll cross type rolling mill. 14. A work roll cloth type rolling mill according to claim 1, a lubricant tank for storing excess lubricant collected by the lubricant supply device, and the lubricant supply. A lubricant circulation system having a pump for supplying lubricant to the apparatus. 15. An extra lubricant collected by the lubricant supply device, wherein at least one of the work roll cloth type rolling mills according to claim 1 is installed so as to be capable of tandem rolling. Rolling equipment comprising a lubricant tank for storing lubricant and a lubricant circulation system having a pump for supplying lubricant to the lubricant supply device. 16. A rolling method for a rolling mill comprising a pair of work rolls and a pair of reinforcing rolls respectively supporting the work rolls, wherein a coolant is supplied to the pair of work rolls from the exit side or the entry side of the rolling mill. Injecting and cooling these, Injecting lubricant to a position on the surface of the reinforcing roll away from the respective contact position between the pair of working rolls and the pair of reinforcing rolls and reinforcing each of the working rolls Lubricating between the rolls, at the same time, in a horizontal plane, such that the axes of the pair of work rolls intersect with the axes of the pair of reinforcing rolls respectively and the axes of the work rolls intersect each other. A rolling method comprising controlling the inclination of the pair of work rolls to control a sheet crown of a rolled material. 17. A pair of work rolls, and a pair of reinforcement rolls respectively supporting the work rolls, wherein the pair of work rolls have their axes crossing the axes of the pair of reinforcement rolls, respectively. And, in a work roll cross type rolling mill that is arranged inclined in a horizontal plane such that the axes of the work rolls intersect with each other, a lubricant is supplied between the pair of work rolls and the pair of reinforcing rolls. A lubricant supply device, wherein the lubricant is:
(A) the coefficient of friction between the work roll and the reinforcing roll is in the range of 0.04 to 0.1, (b) the viscosity is not more than 80 Cst. At 40 ° C., (c) ) Mineral oil and 5% or more synthetic ester as base oil, (d) 0.03-0.5% fatty acid as oiliness improver, (e) 0.1% or more extreme pressure additive A work roll cross type rolling mill characterized by including a lubricating crude oil satisfying. 18. A pair of work rolls, and a pair of reinforcement rolls respectively supporting these work rolls, wherein the pair of work rolls have their axes intersecting with the axes of the pair of reinforcement rolls, respectively. And the work roll cross type rolling mill configured to be inclined in a horizontal plane and to be movable in the roll axis direction of each of the pair of work rolls so that the axes of the work rolls cross each other, A lubricant supply device for supplying a lubricant between the work roll and the pair of reinforcement rolls, wherein the lubricant has the following conditions: (a) a friction coefficient between the work roll and the reinforcement roll is (B) a viscosity of not more than 80 Cst. At 40 ° C., and (c) a mineral oil and 5% or more synthetic ester as a base oil. (D) a lubricating oil that satisfies the following requirements: (d) containing 0.03 to 0.5% of a fatty acid as an oiliness improver, and (e) containing 0.1% or more of an extreme pressure additive. Roll cross type rolling mill. 19. The work roll cloth rolling mill according to claim 17, wherein the lubricating crude oil further contains (f) a surfactant as an emulsifier in an amount of 0.5% or less. 20. A rolling method for a rolling mill comprising a pair of work rolls and a pair of reinforcing rolls respectively supporting the work rolls, wherein a coolant is supplied to the pair of work rolls from the exit side or the entry side of the rolling mill. Injecting and cooling these, while supplying a lubricant between the pair of work rolls and the pair of reinforcement rolls, the axes of the pair of work rolls are respectively relative to the axes of the pair of reinforcement rolls. Controlling the sheet crown of the rolled material by controlling the inclination of the pair of work rolls in a horizontal plane so that they intersect and the axes of the work rolls intersect with each other; The coefficient of friction between the work roll and the reinforcing roll is in the range of 0.04 to 0.1, (b) the viscosity is 80 Cst. Or less at 40 ° C., and (c) mineral oil is used as the base oil. And (d) containing 0.03 to 0.5% of a fatty acid as an oiliness improver, and (e) containing 0.1% or more of an extreme pressure additive. A rolling method using crude oil or an emulsion thereof. 21. A rolling method for a rolling mill comprising a pair of work rolls and a pair of reinforcing rolls respectively supporting the work rolls, wherein a coolant is supplied to the pair of work rolls from the rolling mill exit side or the entrance side. Injecting and cooling these, while supplying a lubricant between the pair of work rolls and the pair of reinforcement rolls, the axes of the pair of work rolls are respectively relative to the axes of the pair of reinforcement rolls. Controlling the inclination of the pair of work rolls in a horizontal plane so as to intersect and the axes of the work rolls to intersect with each other; and controlling the inclination of the pair of work rolls and moving the work rolls in the roll axis direction. Controlling the sheet crown of the rolled material by controlling the amount, the following conditions are used as the lubricant: (a) the friction coefficient between the work roll and the reinforcing roll is 0. (B) a viscosity of not more than 80 Cst. At 40 ° C., (c) a mineral oil and 5% or more synthetic ester as a base oil, and (d) an oiliness improver. A rolling method characterized by using a lubricating stock solution or an emulsion solution thereof, which satisfies 0.03 to 0.5% of a fatty acid, and (e) contains 0.1% or more of an extreme pressure additive. 22. The rolling method according to claim 20, wherein the undiluted lubricating solution further contains (f) a surfactant as an emulsifier in an amount of 0.5% or less.